Hi Speed Expansion

[phatman]

Hello,

There is a fellow on another forum that has the nicest 40 cal 400 grain gas check mold from LBT you have ever seen.
He loads this thing to 2100 fps and gets double caliber expansion with 90% weight retention.

HOW??

Going 2100 I either have almost no expansion or expansion and a leaded barrel:confused:

So please help me out here. I've cast a lot of pistol bullets but they were hard cast SWC for a revolver. My rifle (9.3x62) is making me work for it.

Thanks, John

[turbo1889]

Sounds like he is soft point casting (two alloys, soft alloy in nose with little dipper made from small caliber pistol case and piece of wire and then fill it up the rest of way with hard alloy form bottom pore).

[yondering]

Any chance he's paper patching? That's the way I would go about it (and I am, actually). This can easily be done with a soft alloy for expansion, and still attain that velocity or much higher.

Phatman, I'm getting really great results from paper patching traditional grease groove bullets in my 35 Whelen, which is awful similar to your 9.3. I highly recommend it, and would be happy to share details if you're interested. It removes any velocity limitations of lead bullets: with paper patches the velocity is limited just by chamber pressure, like jacketed bullets, rather than by lube and alloy variables.

[Shiloh]

Any chance he's paper patching?

Thats what I thought. When you soft point cast, is there an actual weld or is there a separation line where the two parts join??

SHiloh

[dubber123]

Something I have just recently tried, (after much prodding by some forum members), is an alloy of 50/50 WW-Pb., water quenched. I really didn't believe a SOFTER alloy could be better at controlling leading at high speeds, but.... Well, they were right. The first loads in a .35 Whelen were 2,600 fps., and the bore is spotless! 1 patch with a little oil, cleanup is done. First loads with a .35 Remington pump were just over 2,100 fps., and again spotless. The guys who suggested this claim this alloy expands nicely also, but I haven't gotten to test that out yet.

[Bret4207]

The question is- What is getting his expansion in? Boolits and bullets expand differently in different mediums. My WW boolits out of a 35 Rem Marlin using a FN 180ish gr boolit at 1650 fps expand nicely in the fine sand of my ballistics research facility (sand pit on my farm). If the sand is wet they expand more. If I stick one in a porky they expand differently and in other mediums differently yet.

My point is that without knowing what he's using for a medium it's tough to say how he's getting the expansion as far as alloy, etc goes. Range and velocity on target make a difference too. I can pretty much guarantee those nifty pics in a lot of ads and magazines weren't made in deer or antelope.

[Bass Ackward]

The question is- What is getting his expansion in? Boolits and bullets expand differently in different mediums. My WW boolits out of a 35 Rem Marlin using a FN 180ish gr boolit at 1650 fps expand nicely in the fine sand of my ballistics research facility (sand pit on my farm). If the sand is wet they expand more. If I stick one in a porky they expand differently and in other mediums differently yet.

My point is that without knowing what he's using for a medium it's tough to say how he's getting the expansion as far as alloy, etc goes. Range and velocity on target make a difference too. I can pretty much guarantee those nifty pics in a lot of ads and magazines weren't made in deer or antelope.



Yep. And meplat size and bullet diameter play a part in it too. Don't believe it? Take a small caliber bullet that is hard and whack it. Then whack an ACWW 45 caliber with something close to the same force. That's why you don't need rock hard bullets to control expansion with larger bores. Strength comes from diameter.

But you can expand (or break up is maybe more appropriate) WDWW of 30 BHN as low as 2200 fps in 45 caliber. You just need to hit denser material to make it happen. It would probably be a little lower with smaller diameters, but I don't use it anymore to tell you.

[Bass Ackward]

Something I have just recently tried, (after much prodding by some forum members), is an alloy of 50/50 WW-Pb., water quenched. I really didn't believe a SOFTER alloy could be better at controlling leading at high speeds, but.... Well, they were right. The first loads in a .35 Whelen were 2,600 fps., and the bore is spotless! 1 patch with a little oil, cleanup is done. First loads with a .35 Remington pump were just over 2,100 fps., and again spotless. The guys who suggested this claim this alloy expands nicely also, but I haven't gotten to test that out yet.


In the olden days, the "Rifle Mix" was 1/10 lead tin. That is 10 - 11 BHN. That has zero antimony and is the finest (although quite expensive) high velocity mix I ever used.

What many people never seem to realize is that it is antimony that causes the problems unless you are overly hard. Then you have to worry about break up.

You want beautiful expansion and HV with less trouble, eliminate antimony, 1/10 is the mix.

[yondering]

1/10 lead tin. That is 10 - 11 BHN.

Are you sure? I just saw a chart a few days ago (and can't remember where now) that listed 10-1 as being much harder than that. I believe it showed 30-1 at 8-9 BHN, and 20-1 at 12-14, similar to ACWW.

I'm not saying you're wrong, just wondering if you've measured the hardness with a reliable method?

[Bass Ackward]

Are you sure? I just saw a chart a few days ago (and can't remember where now) that listed 10-1 as being much harder than that. I believe it showed 30-1 at 8-9 BHN, and 20-1 at 12-14, similar to ACWW.

I'm not saying you're wrong, just wondering if you've measured the hardness with a reliable method?


That's new fangled modern tin. That stuff is invigorated.

I have the old fashion stuff that's a tad stale. Besides, it makes me look good if I quote velocity figures for softer lead. Drives Larry crazy. :grin:

[phatman]

Hello,

Thanks for the help.
I have a little more information.
The bullet he used was by Lead Bullet Technologies, flat nose hunting bullet.
It was fired into water filled milk jugs at exactly 2150 fps.
The lube was LBT Speed Blue.
The alloy was 94% lead 5%tin 1% Ant

By the way, Rotometals sells 20 to 1 (95% lead 5% tin) and says its hardness is a 10. This is the alloy that leaded the hell out of my barrel in 3 shots at 2000 fsp [smilie=b:

Thanks, John

[Bass Ackward]

By the way, Rotometals sells 20 to 1 (95% lead 5% tin) and says its hardness is a 10. This is the alloy that leaded the hell out of my barrel in 3 shots at 2000 fsp [smilie=b:

Thanks, John




While I have had leading numerous times, I have never had any mix that caused leading. Any leading that developed was always caused by me in my reloading procedures or my gun for improperly asking or forcing a mix to do something that it wasn't capable of doing.

See velocity is seldom the cause of leading with a good lube and a smooth bore. The enemy is almost always pressure or the rate of pressure.

What were the circumstances?

[phatman]

I found it, I'm stupid.

My groove diameter is .366 my mold is dropping the bullets at .3658 or so.
So its gas cutting?

I'll get a new mold and try again.

Thanks again guys.
John

[docone31]

You need .368 minimum. Try patching it up to that size.
Might have fun.

[yondering]

I found it, I'm stupid.

My groove diameter is .366 my mold is dropping the bullets at .3658 or so.
So its gas cutting?

I'll get a new mold and try again.

Thanks again guys.
John

Should make a great paper patch bullet, using the information in the PM i sent you.

And/Or, you can lap that mold out to .367"+ without too much difficulty.

[turbo1889]

. . . . When you soft point cast, is there an actual weld or is there a separation line where the two parts join? . . .

If you do it right there is no joint only an area where the dark grey color of pure lead merges into the frosted look of hard three metal alloy run hot. It is all in the timing. First little dipper pore needs just enough time to harden but not cool down very much at all so that when the hot alloy from the bottom pore comes down from above there is a slight mixture layer created where a little bit of the nose metal melts into the base metal and visa-versa.

[357maximum]

Iffin ya take a WD'ed 50/50 ww/pure boolit. Stand that boolit up in a pan of water to the crimp groove or above and anneal the nose quickly with a propane torch you can totally eliminate all that [smilie=b:duopoured-burnt-my-fingers-shtuff[smilie=b:. At 35rem(2100) speeds they will muchroom nicely in a deer sized critter and at 35whelen(2500+) velocities they will mushroom and then shed the nose and act just like a nosler partition. You do not have to "eliminate" the antimony just "reduce" it's percentage to make a nice accurate pleasant to use kill da critter alloy.........and you do not have to jump through hoops and juggle to get it.

I do not recommend this application with HV hollowpoints however...[smilie=b:grinds the burger while it is still on the hoof[smilie=b:.

Good meat gatherin boolits ain't gotta be difficult. :)

The annealing is not neccessarry with this alloy either....unless you are running slow or at extended range. A good flatpointed 50/50 boolit..............flat out getsRdid.

[303Guy]

http://i388.photobucket.com/albums/oo327/303Guy/MVC-468F.jpgIdentical boolits, different speeds into fine sand. That's what I call hold together. Weight retention about 99%.

[phatman]

Thanks, Guys

I knew you would come through for me.

Thanks Dan, I've got the PM and that makes it very clear. Just have to order a few accessories, cant have enough of those.:-)

Thanks again,
John

[yondering]

Identical boolits, different speeds into fine sand. That's what I call hold together. Weight retention about 99%.

I'm sure we've discussed this before, but shooting into sand is meaningless, in relation to how a bullet performs in flesh. It's not even a good comparison between two different bullets. Sand packs hard on impact, and forces expansion the same way as if you shot at a rock, but less severe. That's a whole lot different than flesh which is mostly fluid.

Have you shot those bullets into something more representative, like wet newspaper, or even water? You may get zero expansion, or it may tear the expanded nose portion off. Don't know till ya try it (or shoot animals, that's the best test of all of course.)

[jdgabbard]

Are you sure? I just saw a chart a few days ago (and can't remember where now) that listed 10-1 as being much harder than that. I believe it showed 30-1 at 8-9 BHN, and 20-1 at 12-14, similar to ACWW.

I'm not saying you're wrong, just wondering if you've measured the hardness with a reliable method?

Lyman manual says 11.5 BHN...